The emission of high noise levels and extensive wear of steel wheels and steel rails is a common problem in rail systems, including freight, passenger and mass transit trains. Such problems are directly attributed to the frictional forces generated between the wheel and the railhead during operation of the system. In addition to noise problems and extensive wear of the wheels and rails, negative friction between the two sliding steel surfaces cause slip-stick oscillations. This, in turn, results in inefficient as well as sub-optimum performance.
In order to control friction, it has long been the practice to apply grease or friction control compositions onto the rail, including onto the railhead as well as the sides of the rail. Most notably, such compositions have been applied at curves, inclines, turnouts, switches, etc. Friction control compositions can either reduce or increase the friction when necessary to improve train performance and reduce wear on both the railhead and the train wheels.
In order to increase friction between the train wheel and the rail, the friction control composition is typically placed on the railhead. Applicators used to place friction control compositions onto railheads are called top of rail (TOR) applicators. In normal practice, TOR applicators are periodically spaced along the length of the rail track. The spacing of TOR applicators is typically dependent on the ability of the friction control composition to carried down the rail. Unfortunately, when compared to applicators placed on the side of the rail, TOR applicators, in direct contact with the train wheel, are more likely to be damaged or destroyed by train wheels.
TOR applicators have been developed over the years to address this issue. However, such applicators have proved to be inadequate for a number of reasons. For example, in some prior art applicators, the friction control composition typically does not reach the center of the railhead. As a result, the friction control composition is not effectively carried down the rail. In other cases, substantial amounts of the friction control composition are wasted because the friction control composition ends up leaking down the sides of the rail and off the railhead. In other instances, while prior art TOR applicators place the friction control composition on the railhead, the applicator itself is damaged or destroyed by impact when hit by train wheels. Thus, such TOR applicators of the prior art become inoperable from impact damage.
TOR applicators that effectively place the friction control composition onto the railhead such that the friction control composition is efficiently carried down the track are desired. In addition, such TOR applicators need to be relatively safe from being damaged or destroyed from the impact of train wheels.
It should be understood that the above-described discussion is provided for illustrative purposes only and is not intended to limit the scope or subject matter of the appended claims or those of any related patent application or patent. Thus, none of the appended claims or claims of any related application or patent should be limited by the above discussion or construed to address, include or exclude each or any of the above-cited features or disadvantages merely because of the mention thereof herein.